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Updated: Dec 7, 2025
06:44
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
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Halogen-bonded haloamine trimers - modelling the X3 synthon
1University of Lodz, Faculty of Chemistry, Department of Physical Chemistry, Theoretical and Structural Chemistry Group, Pomorska 163/165, 90-236 Łódź, Poland. justyna.dominikowska@chemia.uni.lodz.pl.
Physical Chemistry Chemical Physics : PCCP
|September 25, 2020
Summary
Haloamine trimers exhibit weaker halogen bond cooperativity than tetramers due to fewer synergy components. This study reveals differences in interaction origins between trimer and tetramer geometries.
Area of Science:
- Supramolecular Chemistry
- Crystal Engineering
- Computational Chemistry
Background:
- Halogen-halogen bonded haloamine trimers model the X3 synthon in nanoarchitectures.
- Halogen bonds in synthons are often cooperative, with synergy effects seen in bromoamine and iodoamine tetramers.
Purpose of the Study:
- Compare cooperativity in haloamine cyclic trimers versus tetramers.
- Investigate the origins of halogen-halogen interactions in these clusters.
Main Methods:
- Comparative analysis of haloamine cyclic trimers and tetramers.
- Energy decomposition analysis (EDA, SAPT) and Kohn-Sham molecular orbital theory applied to dimers.
Main Results:
- Bromoamine and iodoamine trimers show significantly weaker cooperativity than tetramers.
- Interaction energies in dimers are similar, but their origins differ based on geometry.
- Orbital interactions and electrostatic attraction are weaker in trimer-like dimers compared to tetramer-like dimers.
Conclusions:
- Weaker cooperativity in trimers stems from fewer synergy components.
- Differences in interaction origins, particularly weaker orbital and electrostatic contributions, explain reduced cooperativity in trimers compared to tetramers.
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